Urban Transportation and Logistics

214 Ali Gul Qureshi

8.4.4.2 Heuristics Approaches

Earlier heuristics for the SVRP-D were based on some modication of

the well known Clarke- White algorithm (Stewart and Golden 1983; Dror

and Trudeau 1986). Stewart and Golden (1983) also proposed a general-

ized Lagrange multiplier (GLM) heuristics by Lagrangianly relaxing con-

straint Equation (8.20) in the chance constraint model and determining

their best value by solving the relaxed problem as an m-TSP, whereas, in

the recourse constraint model, the penalties were considered as known

optimum value of the Lagrange multipliers. Later, some complex meta-

heuristics were also presented, a few of ...